As we can in Fig., stress-strain curve calculated at 200K and 300K are in accordance with recent calculations, obtained from DFT and MD methods[1]}. Our results show roughly two regimes: A linear-elastic regime up 10% of strain and subsequently, a plastic region
resulting from permanent deformations due to structural bond breaking followed by fracture where stress abruptly drops to zero. Similar trends where obtained
at 400K and 500K where there is a progressive reduction of critical fracture points (Ultimate tensile stress \(\sigma _{US}\)  and critical strain \(\varepsilon _c\) ) One should note that increase in temperature does not significantly influence the values of Young's modulus, but it does affects drastically the critical fracture points in agreement with the kinetic theory of solid fracture [2]}, [3]}, [4]}, [5]}. Those values are compiled in Table  REF . These critical points decrease with increasing temperature. The Young's modulus obtained in a linear regime (5 % deformation) change in the range of \( 154 - 227 GPa.nm \)  for temperatures up to \(1000K\) . Values found for Young's modulus at 200K-700K (where PG structure remains almost unchanged) are close to values found in the literature by using MD calculations and also according to DFT calculations[1]}.
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